Transport refrigeration systems are used with vehicles and mobile containers for temperature control, primarily maintaining goods in preselected temperature ranges. The systems are used in cargo containers on trailers and ships. The systems are used on large commercial trailers, on small vans and delivery trucks, and on all trucks irrespective of size. The systems may be used with passenger vehicles, particularly buses and vans.
Existing transport refrigeration systems come in many forms, shapes, models and sizes, all with different parts. Refrigeration dealers and repair facilities are required to keep large inventories of units and parts, along with large service networks containing highly skilled and highly paid refrigeration mechanics. Transport refrigeration systems are expensive to acquire, operate and maintain. Refrigeration systems must be operated and maintained so that buildings, factories, warehouses, offices, apartments and homes can be continuously used without interruption or discomfort to occupants. When trucks and buses are involved, the downtime for needed repairs and replacements is a major disadvantage and economic loss.
Most trucking direct drive transport refrigeration systems are not capable of holding a constant deep frozen refrigeration when transporting goods in heavily congested traffic areas or in busy multiple drop delivery routes. Frequent stops and multiple door openings while truck engines are idling reduce available refrigeration and require high capacity quick recovery. Secondary power sources or dedicated engines are needed to accommodate deep frozen requirements, even in very small trucks. The secondary power sources or dedicated engines add expense, maintenance and waste to deep freeze refrigerated transports.
In most cases, when trucks having refrigerated cargo containers need refrigeration repairs, it is first necessary to unload the container and transfer the frozen or chilled goods to a cold warehouse or to another refrigerated container.
Needs exist for improved transport refrigeration systems. Needs also exist for improved delivery systems, methods and apparatus for refrigeration, freezing and air conditioning without requiring massive inventories, expert workers and delays in delivering repair, replacement and service parts.